How Many Eternals Could We See In The MCU?
Contains spoilers for the mid-credits scene in "Eternals"
Now that Marvel Cinematic Universe's newest film, "Eternals," has been released, its titular superhero team is now an official part of MCU canon. As the film reveals, the Eternals are superpowered defenders of humanity created thousands of years in the past by a group of godlike deities known as the Celestials. A couple of Celestials have appeared in MCU films prior to the introduction of Arishem the Judge (David Kaye) in "Eternals" — namely, Eson the Searcher in the first "Guardians of the Galaxy," and Peter Quill (Chris Pratt)'s father Ego (Kurt Russell) in its sequel. The Celestials likewise created a distinctly eviler group of super-beings called the Deviants, who the Eternals must stop whenever they pose a threat to Earth.
The "Eternals" movie introduces audiences to 11 different team members from its comic book source material — in which much of this lore was established — including Eros (Harry Styles) in its mid-credits sequence. Multi-film villain Thanos (Josh Brolin) is also technically an Eternal. Naturally, the "Eternals" comics have featured quite a bit more than 12 Eternals in total over the course of their ongoing publication. Given that a considerably higher number of Eternals exist in Marvel Comics continuity, it's quite possible, then, that the MCU could one day introduce more team members still than the 12 featured on-screen thus far.
The MCU won't include every Eternal any time soon, but more are likely
Two days before the movie's premiere, Reddit user AlphaBaymax posted a series of graphics to the "Eternals" subreddit containing every single Eternal introduced in Marvel Comics organized by team, along with pictures and their first comic book appearances. Their list features 50 distinct characters in total. That said, comic book readers know that the Celestials created just over 100 Eternals, meaning that some have yet to be introduced even in comics.
Presuming that the MCU is more likely to incorporate Eternals already established within comic book canon than invent new team members, 38 Eternals remain. If the MCU continues to be a fixture of blockbuster cinema for time immemorial, then all 38 of those Eternals could very well appear in live action one day. More probable, for the time being at least, is a second "Eternals" film introducing, say, three or four of the more prominent team members from the "Eternals" comic book series.
In short, while the MCU of the distant future could theoretically feature over 100 Eternals, 38 of whom could be pulled from the pages of the series' comic book source material, a more likely scenario is a slow trickle of new characters, amounting to a handful of new Eternals every few years for as long as the MCU is sustainable.